The present invention relates to a hand held power tool. More particularly it relates to a hand held power tool which is provided with a safety coupling.
Hand held power tools of the above mentioned type for drilling or impact drilling are known. One of such machines is disclosed in the German document DE-C-30 41 099. In this power tool a switching member which is formed as a movably supported mass is deviated from its rest position during clamping or blocking of the drill. The deviated mass actuates an electric switch which in turn interrupts the current supply to the drive motor of the machine. Due to the small switching forces of the mass which acts as an inertia body, the switch can be formed only as a contactless proximity switch which is relatively expensive. The known device also operates only for turning off of the drive force, and it does not provide mechanical decoupling of the drive source from the tool. Therefore due to the subsequently running motor and also high swinging masses, the housing in the event of the blocked tool still rotates relatively significantly further about the tool axis.